Apparatus for compacting granular material

ABSTRACT

The specification discloses an apparatus for compacting granular material utilizing a die and a lower punch and an upper punch. The upper punch is mounted on a press slide to be reciprocated into and out of the upper end of the die, while the die is floatingly supported and guided in the press and the lower punch mounting is movable in the press between an uppermost ejection position in which a punch mounted thereupon would have its upper end flush with the top of the die and a lowermost fill and compacting position wherein the lower punch is solidly supported on the press bed. A crankshaft in the press has angularly related throws connected to the slide which supports the upper punch and to a bridge that engages the lower punch mounting from beneath. Resilient cushions are employed for floating the die table that carries the die and for controlling relative movement between various parts of the press.

Unite States Patent 1 urley et a1.

'[ APPARATUS FOR COMPACTHNG GRANULAR MATERIAL Related U.S. ApplicationData [63] Continuation of Ser. No. 41,354, May 28, 1970,

abandoned.

[52] U.S. Cl 425/78, 425/352, 425/415 [51] Int. Cl. 82% 3/04 [58] Fieldof Search 425/78, 415, 352, 425/355; lOO/DIG. 35

[56] References Cited UNITED STATES PATENTS 3,132,379 5/1964 Crane425/78 3,353,215 11/1967 Haller 425/355 3,664,784 5/1972 Sibley 425/781,766,265 6/1930 Smith 425/415 X 3,154,812 1111964 l-laller 425/783,191,232 6/1965 Haller 425/415 X 2,499,980 3/1950 Stokes, Jr. et a1.425/352 [4 1 Oct. 9, 1973 Primary Examiner-Robert L. Spicer, Jr.Attorney-Albert L. Jeffers [5 7] ABSTRACT The specification discloses anapparatus for compacting granular material utilizing a die and a lowerpunch and an upper punch. The upper punch is mounted on a press slide tobe reciprocated into and out of the upper end of the die, while the dieis floatingly supported and guided in the press and the lower punchmounting is movable in the press between an uppermost ejection positionin which a punch mounted thereupon would have its upper end flush withthe top of the die and a lowermost fill and compacting position whereinthe lower punch is solidly supported on the press bed. A crankshaft inthe press has angularly related throws connected to the slide whichsupports the upper punch and to a bridge that engages the lower punchmounting from beneath. Resilient cushions are employed for floating thedie table that carries the die and for controlling relative movementbetween various parts of the press.

31 Claims, 22 Drawing Figures PATENTEU 9975 3.734.244

SIEU 03 W 14 Q47) JNvENToQs DONALD L. HURLEY CHARLES R.TALMAG E LJQFFQVS Qlckerf A- orney$ PATENTEUUU B 3.764.244

saw 850$ 14 VFW XNVENTOFZS DONALD L HURLEY CHARLES QTALMAQE PATENTEBUBT91915 3.764.244

NET 03 (I? 1@ 70 F IG I3 FILL SHOE RETRACTED INVENTOQS DONALD L. HuczuavCHARLES. R.TALMA 5E v m JeFFersRmkev-i' v A-Wov-nQys PATENTED BET 9 I973SHE? 13. w M

llllili 22 r /I5 E58 FIG.I8

FIG.I7

EJECTION \Wxeo I INVENTORS DONALD L. HUQLEV CHARLESIZTALMAGEI M defl-ersQmkert PATENTEUUBT 3,764,244

SHEET 13 0? 1a 232 lNvaN-roR-s DONALD LUURLEY F IG f 2 CHARLES RTALMAGEV deFGers Qmkerr Ad-(ovneys PATENTEHUBT 919w 3,764,244

SNEET 1% BF 1 F I6. 22 INVENTORS Domxw L. HURLEY Cumzws QTALMAGEAPPARATUS FOR COMPACTING GRANULAR MATERIAL RELATED U.S. APPLICATION Thisis a continuation of application Ser. No. 41,354, filed May 28, 1970,now abandoned.

This invention relates to an apparatus for producing workpieces bycompacting granular materials and to a press for compacting thematerials.

The compacting of granular materials is well known in the ceramic artand also in the powdered metal art. Many types of compacting presses,both mechanical and hydraulic, have been devised for compacting thegranular materials but, heretofore, the presses have been relativelycomplex to set up and operate, and the prior art presses have not beensufficiently reliable in operation, and have lacked the precision andrigidity necessary to produce precisely sized workpieces at high speed.

Furthermore, many such presses involve the use of mechanical latches andreleasing devices therefor and auxiliary motors or actuators to insurethe proper relative positioning of the parts during operation of thepress.

Still further, many of the presses employ multiple motors for actuatingvarious parts of the dies that are being used in the press and both theuse of latches and the use of multiple motors causes complexity inoperation and control of the press. Through this complexity ofconstruction precision is lost and rigidity of the press structure isoften impaired.

When a part is compacted from granular or powdered material, it usuallyrequires considerable force to remove the compacted workpiece from thedie in which it is formed and, heretofore, either ejection of the partfrom the die or withdrawal of the die from the workpiece is resorted toin removing the workpiece from the die. When ejection is employed insome existing presses the lower punch requires adjustment for effectingthe filling of the die cavity. When withdrawal of the die from theworkpiece is employed in other existing presses a fixed lower punch isemployed, but difficulties are sometimes encountered when flanged partsare to be removed from a die.

With the foregoing in mind, it is a primary object of the presentinvention to arrive at a press configuration which combines theadvantages of both of the aforementioned ejection and withdrawalmethods.

A salient object of the invention is the achievement of precisealignment between the reciprocating slide that carries the upper punchand the floating table that carries the die by aligning and guiding bothmembers on precise guide ways on the press structure.

A further object of this invention is the provision of a press in whichthe lower punch of the die is fixed and solidly supported on the pressbed for compaction, but wherein no adjustment of the lower punch isrequired to establish the fill depth of the die cavity.

In addition, it is an object of the invention to provide a more rigidand hence more precise structural configuration for a press by conveyingthe high compaction loads only through major structural members and overshort distances.

Another object of this invention is the provision of a press in whichthe compacted workpiece is ejected upwardly out of the die using a fixedstroke of the press actuating mechanism thereby eliminating the need forremovable stops for the die which are employed when a die is pulleddownwardly to release a workpiece therefrom.

Another object of this invention is the achievement of the highreliability and durability of a crank-type actuating mechanism in placeof the less durable cams that are used in prior art mechanical presses,while at the same time achieving the desired dwell positions in themovement of the lower punch mounting and floating die table through theuse of resilient cushions and stops.

Still another object is the provision of a press arrangement which iseasy to set up and simple to operate and in which all of the pressmovements are precisely timed relative to each other without thenecessity of complex controls or cams.

Still another object of the invention is the provision of a press whichwill operate rapidly and which is extremely rigid to provide for theproduction of precision parts at high rates of speed.

Still another object of the invention is the provision of a pressarrangement in which a workpiece having stepped contours can befabricated by compaction and ejected from the die cavity withoutbreakage.

Still another object of this invention is the provision of a modularfill shoe and fill shoe actuating mechanism adaptable to a variety ofproduction requirements through the use of a readily interchangeable andadjustable fill shoe actuating cam, a fill shoe mounting that permitseasy interchange of fill shoes of various sizes and shapes adapted tothe needs of the particular part being manufactured, and an adjustablemechanism to provide for changing the dwell time of the fill shoe at thefill position. v

The foregoing objects as well as still other objects and advantages ofthe present invention will become more apparent upon reference to thefollowing detailed specification, taken in connection with theaccompanying drawings, in which:

FIG. 1 is a schematic view showing an arrangement of machines forpracticing the process of the present invention;

FIG. 2 is a perspective view of the press forming the principal machineutilized in the practice of the invention;

FIG. 3 is a fragmentary perspective view showing the drive crankshaft ofthe press of FIG. 2;

FIG. 4 is a schematic fragmentary view, partly in section, showing otherparts of the press structure;

FIG. 5 is a fragmentary perspective view showing a powder feed mechanismfor use with the press;

FIG. 6 is a fragmentary view looking in from the right side of FIG. 5showing adjustments pertaining to the powder feed mechanism and theactuating cam for the powder feed mechanism;

FIG. 7 is a fragmentary perspective view showing a typical adjustmentutilized in the press structure;

FIG. 8 is a schematic vertical sectional view through the press with theparts thereof displaced from true position for the sake of clarity;

FIG. 9 is a view of the press partly in section at the point in thepress cycle where the die cavity commences to fill with powder;

FIG. 10 shows the relative positions of the throws of the crankshaft forthe FIG. 9 position of the press parts;

FIG. 11 schematically shows the press at the end of the fill cycle FIG.12 shows the positions of the throws of the crankshaft pertaining to theFIG. 11 position;

FIG. 13 is a view showing the press parts when the fill shoe has beenretracted from filling position;

FIG. 14 shows the crankshaft throw positions pertaining to the FIG. 13position;

FIG. 15 is a view showing the press parts at the end of a compactioncycle;

FIG. 16 shows the positions of the crankshaft throws pertaining to theFIG. 15 position;

FIG. I7 is a view showing the press parts during the ejection of acompacted workpiece therefrom;

FIG. I8 shows the crankshaft throw positions pertaining to the FIG. 17position;

FIG. 19 is a view showing the press at the end of the workpiece ejectionstroke;

FIG. 20 shows the crankshaft throw positions pertaining to the FIG. 19positions;

FIG. 21 is a schematic vertical sectional view through a modifiedconstruction with the parts of the press displaced from the trueposition therof for the sake of clarity; and

FIG. 22 is a view from the front of the press of FIG. 21 and partly insection.

BRIEF SUMMARY OF THE INVENTION The press of the present invention isconstructed with a head and a bed and uprights extending therebetweenwith a slide guided on the uprights and with a lift out bridgevertically reciprocable in the press bed. A crankshaft in the press headhas angularly related throws connected to the slide and to the bridgefor reciprocation thereof in timed relation.

A die table is floatingly supported above the bed guided upon the samepress uprights as is the slide, and is adapted for supporting a tubulardie. A lower punch support beneath the die table supports a lower punchextending into the die from below. An upper punch for the die is mountedon the slide and is adapted to enter the die from above.

Resilient cushions provide a floating support for the die table. Othercushions urge the lower punch support toward an upper position whereinit abuts the die table, while the die table also engages a stationaryabutment when in an upper position.

Filling of the cavity of the die is accomplished by moving the lowerpunch support downwardly to a stopped position against the press bedwhere it remains while material is compacted against the lower punch bythe upper punch. The exact amount of fill is controlled by moving thedie table downwardly at the same time as the punch support but a lesserdistance.

Ejection of the compacted workpiece is accomplished when the lower punchsupport and the die table are in their uppermost positions at which timethe upper end of the lower punch and the upper end of the die arecoplanar with the upper side of the die table. With the die table andlower punch in their uppermost positions, a fill shoe reciprocates intoposition over the die to displace the compact from its ejected positionover the die area and deliver powder thereto when the lower punch movesdownwardly, The fill shoe moves out from over the die when the upperpunch descends for compaction.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings somehwatmore in detail,

in FIG. 1, 10 is a press for the compacting of powdered, or granulatedmaterials, such as metal, or ceramic, or the like, and 12 is a sinteringor curing oven. Reference numeral 14 designates a sizing or coiningpress and I6 is a receiver for finished parts.

The press 10 is adapted for cycling continuously and material is fedthereto on each cycle from a supply hopper 18 via a feed, or fill shoe20, which moves into the work space when the press slide 22 retracts andmoves out of the work space when the slide advances. The shoe 20 isarranged to reciprocate into the work space at the time that a workpiececompacted on the previous press cycle has been ejected from the die andis resting on top of the die so that it will be pushed out of theworking space by the inward movement of the feed shoe and be delivered,as by sliding down an incline 24 to a bin or to a conveyor 25 by meansof which it is conveyed through sintering or curing oven 12.

The cured, or sintered, workpiece may then be placed between the diemembers 28 of the coining, or sizing, press 14 and struck, or pressed,or trimmed, to the desired final size and/or configuration. Thecompleted workpiece is delivered to receiver 16, which may be a box, orthe like.

The press, generally indicated at 10 in FIG. I, will be seen in FIG. 2to comprise a head 30, a bed 32 and uprights 34 extending therebetween.On top of head 30 is a drive motor 36 which drives a fly wheel 38 as bymeans of belting 40. Fly wheels 38 and 39 are mounted on a shaft 42,together with a pinion 44. Pinion 44 meshes with a gear 45 on a countershaft 46. Mounted on counter shaft 46 is a clutch-brake mechanism 48,which is employed for interrupting or establishing the drive train inthe press. The output side of the clutchbrake device 48 is connected ina suitable manner with a crankshaft 50 rotatably mounted in the presshead.

Turning now to FIG. 3, it will be seen that a fixed stroke actuatingmeans is provided. The crankshaft 50 has gears 52 thereon which aredriven by suitable gearing from the output side of clutch-brake device48. The crankshaft 50 may have one gear 52 at one end but, preferably,is provided with a gear 52 at each end.

The crankshaft is supported in bearings 54 fixed in the press head andhas a center throw 56 and two side throws 58. The two throws 58 are thesame size and are identically located circumferentially of thecrankshaft while throw 56, which is usually of a different size thanthrows 58, is located on the crankshaft in about the middle of thelength thereof and in circumferentially trailing relation to throws 58.In the present case, throw 56 trails throws 58 at an angle of 75.

Throw 56 is connected to slide 22 by connecting means which includes theconnecting rod 60 embracing throw 56. Slide 22, as will be seenhereinafter, is advantageously adjustable in length to determine thelower limit position of an upper punch member mounted on the undersideof slide 22.

Each of throws 58 is connected with a respective pull rod 64 by way ofconnecting rods 66 and connector members 68, with each connector memberbeing attached to the upper end of a respective pull rod 64 andpivotally connected to the respective connecting rod.

FIG. 4 shows some of the press parts below the press head. In this viewit will be seen that pull rods 64, at their lower ends, are connected toa lift out bridge member 70 which extends transversely of the pressbeneath the upper flange 72 of press bed 32. Lift out bridge 70 is thusarranged to reciprocate in the vertical direction as crankshaft 50rotates and by an amount which is determined by the throw of crankshaftthrows 58. Furthermore, the reciprocation of lift out bridge 70 and thereciprocation of slide 22 will be in precisely timed relation to eachother in conformity with the angular relation of throws 56 and 58.

The slide 22 is guided on uprights 34 and between slide 22 and upper bedflange 72 is the working space of the press. Disposed in this space is adie table 74 which is guided on the press uprights 34. Die table 74 isadapted for being entered from the top by an upper punch member carriedon the underside of slide 22. The die in space 76 of table 74 is adaptedfor being entered from below by a lower punch member supported on apunch support structure which includes a post 78 located on the axis ofthe press. support connected Connected with die table 74 are four rods80 which extend downwardly through upper bed flange 72 and two of whichhave rod extensions 101 which abuttingly engage a flange plate 82secured to the lower end of the lower punch suppoRt post 78. Rods 80, aswill be seen hereinafter, are adjustably connectzd to die table 74.

Also connected to die table 74 are adjustable abutment rods 84 adaptedto abut the upper ends of cushion rods 86 that extend downwardly throughbed flange 72 and lift out bridge 70 to pneumatic cushion cylinders 88.

FIG. 4 will also show cushion cylinders 90 carried on the underside oflift out bridge 70 and biasing pins 92 in the downward direction. Pins92 are adapted for engaging flange plate 82 and for pushing the flangeplate down against other pneumatic cushions 94.

The aforementioned fill shoe 20 and the actuation thereof is shown morein detail in FIGS. 5 and 6. In FIGS. 5 and 6, it will be noted that thefill shoe is in the form of a generally rectangular metal outer frame100 having a relatively thin sheet metal cover 102 on top and may havean optional screen 104 at adjustable levels inside. The downwardlyopening box 20 thus formed is connected by side links 106 to shaft 108carried by a reciprocating plate 110 which is guided in its motion intoand out of the working space in the press by guides 112 and guide rods113. The box is adapted for being drawn out of the working space of thepress by a link 114 pivoted at one end to plate 1 and at the other endto the lower extremity ofa swinging arm 116.

Arm 116 at its upper end is pivotally mounted on a shaft 118 secured tothe adjacent upright of the press in any suitable manner. Close to thepivot axis of arm 116, the arm carries an actuating roller 120 facingthe press. Cam follower 120 is adapted for engagement by a cam 122adjustably carried on the adjacent portion of slide 22. It will beevident that as slide 22 goes downwardly, arm 116 will be cammed in adirection to retract the fill shoe from the working space of the presswhile, upon retraction of slide 22, air cylinder 111 will act on arm 116so as to keep roller 120 against cam 122 and will thus return the fillinto the work space as soon as roller 120 runs off the high part of cam122. Adjustment of the cam 122 on slide 22 provides for timing of themovement of the fill shoe with respect to the slide movement.

At the lower end of arm 116 the connection thereof with link 114 is byway of block 124 and adjustable stop screw 126. The block 124 may befreely slidable in slot 128 of link 114 thereby to provide for dwellperiods of the fill shoe at each limit of its travel.

Acting between plate 110 and levers 131 which are fixed to shaft 108 arethe spring means 130 which maintain the till shoe pressed downwardlyagainst die table 74, thereby to prevent loss of material from the fillshoe.

The fill shoe also embodies a bumper element 132 on its outer end whichpushes the workpiece compacted on the previous cycle of the press out ofthe work space when the fill shoe advances.

It will be seen that the fill shoe can readily be replaced by another ofa different size, if so desired, so that the opening in the bottom ofthe fill shoe can be made to match the fill shoe to the die cavity.Leading from hopper 18 is a flexible fill tube 134 that connects withthe space in the flll shoe through the top wall of the fill shoe so thatthe fill shoe is always supplied from the hopper with the granulatedmaterial which is to be supplied to the die cavity.

It has been mentioned as shown in FIG. 4 that rods are adjustablyconnected to die table 74 to adjust the upper limiting stroke positionof the die table, and that abutment rods 84 are adjustable in die table74 to adjust its lower limiting stroke position. A typical adjustingarrangement comprises threaded portion on rods 84 engaged by nuts 87rotatable in table 74 but held against axial movement therein. Nuts 87are rotated in any suitable manner, as by a worm and wheel structure ofthe nature illustrated in FIG. 7. In FIG. 7, worm gear 89 is adapted forrotation by worm 91 which may be adjusted by hand wheel 93 or by amotor. Worm gear 89 is connected to a nut 87. The nut in turn carries agear meshing with a gear 97 rotatable in table 74 and meshing withanother gear 99 attached to another nut 87. The adjustment described andillustrated is typical of adjustments employed in the press for theadjustment of various rods so that two, or more, rods can be adjusted inunison and by the same amount, merely by adjusting a selected onethereof.

Substantially the entire press is schematically shown in vertical crosssection in FIG. 8, with various parts of the press displaced for thesake of clarity in comprebending the structure and operation of thepress.

The press of FIG. 8 also shows a certain construction located beneaththe bed of the press which can form a part of the press structure asmanufactured or which can be added thereto subsequent to the pressmanufacture. The equipment shown below the press bed in FIG. 8 isoperative for certain modes of operation of the press but, on otheroccasions, is inoperative.

Wherever applicable, the same reference numerals have been employed inFIG. 8 that have been employed in connection with the figures previouslydescribed. FIG. 8, however, shows certain parts of the press structurethat are difficult to ascertain from FIGS. 1 to 7.

In particular, FIG. 8 shows an alternate adjustable connection of rods80 with table 74. This adjustable connection is represented by threadsat but it will be understood that the adjustable connection of rods 80with table 74 would be of the type illustrated in FIG. 7.

An alternate connection of abutment rods 84 with table 74 is indicatedas adjustable by the threads 142.

FIG. 8 will show that rods 80 have abutment means 144 thereon in theform of collars which abut the underside of upper flange 72 of bed 32 ina certain uppermost position of the said table.

FIG. 8 will also show that the die carried by the die table, anddesignated at 146, is a tubular member with the upper surfacesubstantially flush with the surface of table 74. FIG. 8 also shows thatthere is supported on the lower punch support member 78, a spacer block148 and a lower tubular punch member 150 which extends upwardly into die146 from below. The upper punch member is shown at 152 mounted on heunderside of slide 22.

The lift out bridge 70 connected to the lower ends of pull rods 64 willbe seen to have an upwardly facing abutment at 154 which engages thepunch support structure 78 to lift it to its uppermost position in whichit is illustrated in FIG. 8. It will also be noted in FIG. 8 that theflange plate 82 which is connected to the lower end of the punch supportstructure 78 is engaged by downwardly facing abutment means 156 on rods101 so that the die and lower punch 150 are fixed in a predetermineduppermost position when crankshaft throws 58 are at top dead center and,furthermore, with the upper surfaces of the die and the lower punchflush so that fill shoe can freely slide thereacross and also so thatthe previously made compact can be displaced from the die area by theinward movement of the fill shoe.

Two of the rods 80 in FIG. 8 have extension rods 103 which extenddownwardly through lower bed flange 160 of bed 32 and through a firstupper floating table 162. Floating table 162 has attached to the lowerside thereof an adjustable nut arrangement 164 which is threaded on arod 166 that extends upwardly completely through punch support structure78 and into punch 150 and carries a core element 168 on the upper end.In the arrangement illustrated in FIG. 8, rods 103 are fixedly connectedto upper floating table 162. Rod 166 is also fixed to table 162 so thatthe die table 74 and core element 168 move together maintaining theupper end of core element 168 flush with the upper surface of die 146.When crankshaft throws 58 are at top dead center the top surface oflower punch 150 also becomes flush with the top surfaces of die table 74and core element 168. V

Upper floating table 162 is provided with pneumatic cushions 170 betweenit and the lower flange 160 of bed 32 and is also provided withpneumatic cushions 172 between it and a lower floating table 174.Between floating table 174 and a lowermost table structure 176 arefurther pneumatic cushion means 178. Lowermost table 176 is adjustablymounted on rods 180 carried by and descending from lower bed flange 160.For connection of table 176 to rods 180, the rods are threaded and carrynuts 184 beneath the table 176. Nuts 184 may be connected by a chain 186adapted for adjustment by hand wheel 188 or motor so that all of thenuts 184 can be adjusted at one time.

The cushions 170, 172 and 178 can be provided with air under pressure toprovide for collapsing thereof upon the exertion of a certain axialforce thereon, or they can be exhausted of pressure in which case theywill collapse under the application of substantially no force. In FIG.8, as illustrated, cushions 170, 172 and 178 are not pressurized. Forvarious modes of operation, as will be explained hereinafter, thecushions 170, 172, and 178 will be pressurized in certain combinations.

In FIG. 8, as mentioned, crankshaft throws 58 are at top dead center andcrankshaft throw 56 is behind dead center. Under these circumstances,the previously compacted workpiece 151 has been ejected and is restingon top of the lower punch member 150 and will be pushed out of the diearea when fill shoe 20 enters the working space. As the crankshaftcontinues to rotate, lift out bridge 70 will commence to move downwardlyand when it does move downwardly, the combined weight of die table 74and the punch supporting structure 78 will being about collapsing ofpneumatic cushions 94 which are acting upwardly on flange plate 82.

When, however, rods 84 engage the upper ends of rods 86, the weight ofthe die table 74 becomes supported on its cushions 88 and the weight ofthe punch support structure 78 is not large enough to continue thecollapsing of cushions 94. The lift out bridge 70, however, continues tomove downwardly and pins 82 carried thereby will engage flange plate 82and cause it to move downwardly, together with the punch supportstructure and to cause collapsing of cushions 94.

This movement of the punch supporting structure 78 will continue untilthe downwardly facing abutment 190 thereon engages member 192 supportedon bed flange 72, causing the punch support structure to come to a haltin a solidly supported position. During this downward movement of thepunch support structure, lower punch 150 is drawn downwardly in die 146and forms a cavity which fills with granular material from the fillshoe. Fill shoe 20 was advanced inwardly into filling position by upwardmovement of slide 22 prior to the initiation of the downward movement ofpunch 150 in the die means.

After the punch support structure 78 comes to a halt, lift out bridge 70continues to move downwardly and, during this further movement, cushionmeans pertaining to pins 92 will yield to permit the lift out bridge toovertravel in the downward direction.

The slide 22 commences to advance downwardly when throws 58 are 75degrees beyond their top dead center position so that after punchsupport structure 78 bottoms on member 192, fill shoe 20 wil beretracted and upper punch member 152 will enter the die from above andwill compact material therein. After throw 56 has passed its bottom deadcenter position and slide 22 commences to retract, lift out bridge 70will be back to the position where it engages abutment means 154 of thepunch support structure 78 which will cause vertical movement of punchin the die to eject the compacted workpiece from the die.

During the pressing operation, cushions 88v yield in conformity with thedownward force exerted on die 146 by frictional engagement of thematerial being compacted therein and this downward movement isaccompanied by corresponding downward movement of core element 168which, in this mode of operation of the press, is fixed to the die.

During ejection, the die table 74 and, therefore, the die 146 and coreelement 168 will be returned to their uppermost positions by engagementof abutment means 156 on rods 101 with flange plate 82 connected to thelower punch support structure 78.

The arrangement provides for full press tonnage to be exerted on thecompact with the lower punch firmly supported and with the die floating.The arrangement alos provides for the application of about half the fullpress tonnage for ejection of the compact. It will be noted tht nolatches, cams, or auxiliary drive arrangements are required, but theentire operation of the press is carried out by availing of a singlecrankshaft having two throw arrangements thereon angularly related toprovide for reciprocation of the slide 22 and the lift out bridge 70 intimed relation to each other.

In the foregoing description of a cycle of the press, the core rod 166was fixed to die table 74 by the nuts 81 an 83 threaded on rod 103 andon opposite sides of upper floating table 162.

Other modes of operation of the press, however, are possible where thecore rod and floating die table move independently of each other. In onecase, the core rod may take a greater floating movement than the dietable and in another case, the core rod may take a floating movementless than that of the die table. In one case of independent movement ofthe core rod and die table, the core member, represented by numeral 168in FIG. 8, must be in place for the filling of the cavity and then beout of the powder fill before compaction commences.

According to the present invention, an upper core member mounted on theslide is employed to force the lower core member downwardly prior tocompaction. The adjustable nut 164 is availed of for this type ofoperation to insure that the upper end of core member 168 is flush withthe floating die table after ejection. The upper position of the coremember is, in this case, determined by movement of the lower floatingtable 174 upwardly by the pneumatic diaphragms 178.

The table 174 is forced by the diaphragms 178 against the shoulders 181on rods 180 which are fixed to and descend from lower flange 160 of thepress bed 32. Nuts 81 are adjusted down against the top of upperfloating table 162 when it is in its uppermost position, while nuts 83are adjusted downwardly away from table 162 a sufficient distance topermit the table to float.

In this manner, the core member 168 is held flush with the upper surfaceof the floating table after ejection of the workpiece and untilcompletion of the filling of the die cavity but when the upper coremember carried on the press slide, enters the die cavity, it will forcelower core member 168 downwardly against the bias of cushions 178.

In the event the core rod 166 is to float more than the floating dietable 74, adjustments as mentioned before are made so that the coremember 168 is in the proper position for ejection of a compact and forfilling of the cavity. Nuts 83 are adjusted up against the bottom offloating table 162 while nuts 81 are adjusted upwardly away fromfloating table 162. Fluid diaphragms 170 are maintained under pressureto press table 162 against the lower nuts 83. Diaphragms 170 in thiscase insure that the core member will be pulled out of compacts afterthe compacts are ejected.

In case the sitaution is such that it is not important for core member168 to be flush with the die table during ejection and filling, bothnuts 81 and 83 can be adjusted away from upper floating table 162.

A still further mode of operation of the press requires core rod 166 tobe held stationary during connection. This type of operation is obtainedby movement of the bottom adjustable table 176 upwardly until it abutsthe lower end of core rod 166 at 177. Adjustable nut 164 can be adjustedto insure that the upper end of the core member is flush with hefloating die table at the fill level. Lower nuts 83 are then adjusted upagainst the bottom of uppwr floating table 162, while the upper nuts 81are adjusted upwardly away from the said table. The air diaphragms serveto pull the core member out of the compact and hold upper floating table162 firmly against the lower nuts 83.

In still another type of operation, core rod 166 floats downwardlyduring compaction to a positive stop. In this case, with the floatingtable at the fill level, nut 164 is adjusted until the upper end of coremember 168 is at the desired level. The air diaphragms 178 arepressurized and hold lower floating table 1-74 up against the shoulders181 on rods 180. The lower adjustable table 176 is adjuated for thedesired gap between the lower end 177 of the core rod and the uppersurface of bottom adjustable table 176.

Upper nuts 81 are adjusted downwardly against the top of upper floatingtable 162 to serve as an upper limit for the core rod and core member,while lower nuts 83 are adjusted downwardly away from floating table162.

During compaction, core rod 166 floats downwardly against the bias ofdisphragms 178 until the lower end 177 of the core rod abuts bottomadjustable table 176 which halts movement of the core rod and coremember and solidly supports these elements during further compaction.Bottom adjustable table 176 is designed so that it will sustain at leastone half or more of the rated press tonnage. If it is desired for theupper end of core member 168 to be flush with the floating die tableduring ejection and at the start of the cavity fill, the diaphragms 170and 172 are employed.

In this case, the upper nuts 81 are adjusted so that diaphragms 172 holdupper floating table 162 against the said upper nuts 81 and adjustmentof nuts 164 insures that the upper end of core member 168 is flush withthe upper surface of the die table.

If the floating die table moves downwardly to its fill level, the corerod and core member on the upper end thereof also moves downwardlythereby to maintain the aforementioned flush condition. When the lowerpunch starts downwardly for filling the die cavity, a valve is actuatedand pressure is thereby released from diaphragms 172, while diaphragms170 are at this time pressurized. This deenergization of diaphragms 172and energization of diaphragms 170 forces upper floating table 162 andcore rod 166 downwardly to a stopped position against lower floatingtable 174 which establishes the fill level for the core member mountedon the upper end of the core rod.

It will be appreciated that all of the modes of operation of the pressdescribed above are carried out without the use of cams, mechanicallatches, and release mechanisms therefor, and that, when necessary, the

core rod can be solidly supported for compaction at high tonnagethereagainst.

A modification of the press is shown in FIGS. 21 and 22, wherein afloating table is provided carrying a second lower punch. The purpose ofthis modification is to aid the ejection of flanged parts from the die.Under the high compaction pressures developed by the press all.verticalsurfaces of the compacted part are forced into tight frictional contactwith the walls of the die, outer punch, and core member. To preventbreakage of thin flanges during part ejection, it is necessary that theouter punch members move upward with the part to provide support for theflanges against frictional resistance. This function may be accomplishedthrough

1. A press for compacting granular materials comprising, in combination,a fixed mechanical stroke actuating means for providing tworeciprocating motions having a fixed displacement relationship to eachother, a floatable die table provided with a number of dwell positions,cushion means for controlling an adjustable stroke for said die tableand lower punch means operable by said fixed mechanical stroke actuatingmeans, stop means for providing fixed dwell positions for said dietable, and upper punch means actuated by said fixed mechanical strokeactuating means for reciprocating said upper punch means in apredetermined nonvariable sequence with said die table and lower punchmeans.
 2. A press for compacting granular material comprising, incombination, fixed mechanical stroke actuating means including a firstand a second reciprocating mechanism with a predetermined displacementrelationship, a floating die table provided with a number of dwellpositions, cushion means for controlling adjustable strokes for said dietable and lower punch means carried by said press, said lower punchmeans operable with respect to said die table to support compactingloads, said cushion means, and lower punch means actuated by said firstreciprocating mechanism of said fixed mechanical stroke actuating means,stop means cooperating wIth said cushion means for providing dwellpositions for said die table ad lower punch means, and upper punch meansactuated by said second reciprocating mechanism for cooperation withsaid die table and lower punch means.
 3. A press according to claim 2wherein the lower punch means is reciprocated over a fixed stroke lengthwherein said length is established by cooperating cushion and stop meansso that the lower punch stroke is less than the stroke of the fixedstroke actuating means.
 4. A press according to claim 2 wherein anadditional surrounding punch means is provided in association with saidlower punch means for supporting flanged parts and supportedindependently from said lower punch means.
 5. A press according to claim4 wherein the additional surrounding punch means is operable by the saidfirst reciprocating mechanism in cooperation with additional cushion andstop means.
 6. In a press for compacting granular materials and having ahead and a bed and uprights extending therebetween, a die table adaptedto support a die on a vertical axis, punch support means beneath saiddie table adapted to support lower punch means extending into said diefrom below, a vertically reciprocable slide above said die table adaptedto support upper punch means for entering said die from above, said dietable and punch support means having uppermost positions wherein theupper ends of said die and lower punch means are disposed in the planeof the top of said die table, a downwardly facing stationary firstabutment operatively engaging said die table in its uppermost positionand a downwardly facing second abutment on said die table operativelyengaging said punch support means when said die table and punch supportmeans are both in the uppermost positions thereof, a lift out bridgebeneath said punch support means vertically reciprocable betweenuppermost and lowermost positions, an upwardly facing third abutmentengageable with said punch support means for raising the punch supportmeans to the uppermost position thereof, upwardly acting first cushionmeans associated with said die table and permitting the die table toyield downwardly during compaction, second cushion means acting upwardlyon said punch support means, a downwardly facing fourth abutment on saidbridge engageable with said punch support means upon a predetermineddownward travel of said bridge from its uppermost position and thirddownwardly acting cushion means supporting said fourth abutment on saidbridge, an upwardly facing stationary fifth abutment engageable withsaid punch support means in a predetermined lowermost position thereofspaced from the said uppermost position thereof a distance less than thedistance between said uppermost and lowermost positions of said bridge,and drive means connected to said slide and said bridge operable toeffect reciprocation thereof in timed relation to each other.
 7. A pressaccording to claim 6, in which said first cushion means yields at a loadgreater than the weight of said die table and parts carried therebywhile said second cushion means yields at a load greater than the weightof said punch support means and parts carried thereby and less than thecombined weights of said die table and said punch support means and theparts carried thereby.
 8. A press according to claim 7, wherein a sixthabutment means is spaced upwardly from said first cushion apredetermined first distance to establish the fill level of said dietable.
 9. A press according to claim 8, in which said fourth abutment isspaced upwardly from said punch support means a second predetermineddistance to provide dwell time for positioning the fill shoe over thedie.
 10. A press according to claim 9, in which said punch supporttravels upward from said fifth abutment to a predetermined upperposition for work product ejection.
 11. A press according to claim 6, inwhich said drive means comprises a crankshaft having first throw meansoperatively connected to said bridge and second throw means angularlyrelated to said first throw means and operatively connected to saidslide.
 12. A press according to claim 11, in which said first throwmeans leads said second throw means by an angular interval that dependsupon the relative strokes of the two throw means and the predeterminedtiming relationship within the press mechanism.
 13. A press according toclaim 6, which includes a supply hopper for material to be compacted, afill shoe open on the bottom and pressed against the top face of saiddie table and connected to said hopper to receive material therefrom bygravity, means for advancing said fill shoe into fill position over saiddie during upward movement of said slide and after upper punch meansthereon is out of the vertical range of said fill shoe and said dietable and punch support means are in said uppermost positions thereof,and means for retracting said fill shoe from fill position duringdownward movement of said slide after said punch support means reachessaid lowermost position thereof and before the upper punch means comeswithin the vertical range of said fill shoe.
 14. A press according toclaim 13 in which said means for advancing and retracting said fill shoecomprises an arm pivotally supported at one end on the press andoperatively connected at the other end to said fill shoe, a cam on saidslide, and a cam follower on said arm engaging said cam.
 15. A pressaccording to claim 14, which includes actuating means continuouslyurging said fill shoe toward fill position, said cam and cam followeracting in opposition to said actuating means.
 16. A press according toclaim 15, in which said cam is adjustable and easily replaceable withanother cam of modified contour on said slide to adjust the timing ofsaid fill shoe movements.
 17. A press according to claim 13, in whichsaid fill shoe is readily interchangeable with other fill shoes ofdifferent size.
 18. A press according to claim 11, in which said dietable includes sixth abutment means adapted to engage said first cushionmeans, said sixth abutment means being adjustable on said die table toadjust the length of travel of the die table from the uppermost positionthereof downwardly to the position where it is supported by said firstcushion means.
 19. A press according to claim 11, in which said firstabutment comprises the bed of the press, said die table having rod meansadjustably carried thereby and extending downwardly into said bed andhaving collar means thereon for engagement with the bed in saiduppermost position of said die table to establish the dwell position ofsaid die table for ejection of the work product.
 20. A press accordingto claim 19, in which said second abutment comprises a flange on saidlower punch support means extending laterally beyond said rod means andsaid rod means having downwardly facing shoulder means for engagementwith said flange to maintain said lower punch support means in fixedrelationship to the die table as said die table descends from a dwellposition for ejection of the compacted material to a dwell position forfill.
 21. A press according to claim 19, in which said fifth abutmentcomprises said press bed whereby said punch support means is solidlysupported in the said lowermost position thereof to receive compactingloads.
 22. A press according to claim 15, which actuates a lower corerod within said lower punch support means, said core rod extendingdownwardly through said punch support means and through said bed, saidcore rod having an uppermost position wherein the upper end of the coremember carried thereon is disposed in said plane of the top of said dietable, and means beneath said bed connected to said core rod foradjusting the axial position of said core member.
 23. A press accordingto claim 22, in which the said means connected to said core rodcomprises means adjustably connecting the core rod to said die table formovement in controlled relation therewith.
 24. A press accordiNg toclaim 22, in which the said means connected to said core rod comprisesan adjusting nut threaded thereon, an upper table beneath said bed towhich the adjusting nut is rotatably connected, rod means connected tosaid die table and extending therefrom through said bed and said uppertable, stop nuts adjustable on the rod means on opposite sides of saidupper table, fourth cushion means disposed between said bed and saidupper table, said fourth cushion means being adapted to be supplied withair under pressure to bias said upper table downwardly, fifth cushionmeans operable when energized to urge said upper table upwardly, saidcushion means to be exhausted to remove said bias from the said uppertable.
 25. A press according to claim 24, in which said core rod extendscompletely through said adjusting nut, and a bottom table adjustablysuspended from said bed disposed below the lower end of said core rod afourth distance and is adapted to abut the said lower end of the corerod and halt the said core rod in a predetermined lower positionthereof.
 26. A press according to claim 25, which includes a lower tablebetween said upper table and bottom table and through which said corerod extends, stationary rods dependent from said bed and extendingthrough said upper and lower and bottom tables, shoulders on saidstationary rods above said lower table for abutment therewith, and sixthcushion means acting between said bottom table and said lower table forproviding a floating action for said core rod during compaction.
 27. Apress according to claim 2, which includes a punch support table beneathsaid die table upon which a second lower punch can be mounted, saidsecond lower punch extending upwardly into said die, punch support tablehaving an uppermost position wherein the upper end of said second lowerpunch is disposed in the said plane of the top face of said die tableand also having a lowermost position and floating against a furthercushion when moving downwardly toward said lowermost position, said dietable is floating on cushion supports while punch support table isforced down against adjustable stops on said bed flanges, and abutmentrod means adjustably mounted on said die table and engaging said punchsupport table with rod elements adjustable connected to said punchsupport table and extending downwardly through the bed and against thelower punch mounting flange when both said die table and said punchsupport table are in the uppermost positions thereof, so that thepunches mounted on the lower punch support member and on the lower punchsupport table will be disposed in said plane of the top of said dietable.
 28. A press according to claim 22, in which said first cushion isdisposed so that said die table moves downwardly a predetermined firstamount from its said uppermost position before it engages said firstcushion to establish its fill position and to provide floatingresistance during compaction.
 29. A press according to claim 22, inwhich said punch support means moves downwardly a predetermined secondamount after said first amount before engaging said second cushion meansfor establishing the fill position of said punch support means, and toprovide floating resistance during compaction.
 30. A press according toclaim 5, wherein said additional surrounding punch means is carried by afloating table.
 31. A press according to claim 6 provided with a fillshoe mechanism and with an actuating linkage and having an adjustablestop in said actuating linkage for mechanically controlling a variabledwell time of the fill shoe over the die.